1. Field of the Invention
The present invention relates generally to a power window apparatus and, more particularly, to a power window apparatus for opening the windows of an automobile by a manual operation when the automobile has been submerged in water by for some reason.
2. Description of the Related Art
In generally known power window apparatuses for use in automobiles, the window operating unit is arranged in the door pocket of the driver's side door, each of the door pockets of the passenger side door, or driver's side door and the door pockets of the driver's side door, passenger side door, and the rear seat door.
Each of these operating units in each of the known power window apparatuses comprises a window open switch, a window close switch, a motor for window opening/closing at the time of rotation, and a motor driver circuit for driving the motor by switching between the motor rotational directions according to the operations of the window open switch and the window close switch.
If an automobile equipped with such a power window apparatus has been submerged in water for some reason and the water gets inside the automobile, the water also gets in the door pocket in which the window operating unit is located, eventually submerging the window open switch and the window close switch. If the window open switch and the window close switch are submerged, it becomes difficult for the contacts used in these switches to maintain electrical isolation. If this happens, although each contact is in the break state, the water between the contacts forms a comparatively small resistance which causes the motor driver circuit to operate erroneously, opening or closing the window out of control. In addition, in such a state, because the motor driver circuit block including the window open switch does not operate correctly, operating the window open switch does not make the window open, making it difficult for those trapped inside the submerged automobile to escape.
Recently, for the purpose of eliminating the above-mentioned problem, a power window apparatus has been proposed by the applicant hereof in which a window operating unit arranged in the door pocket on the driver's seat is connected to a submersion detector and a drive control circuit for anti-flooding measures.
The above-mentioned proposed power window apparatus, if an automobile equipped therewith has been submerged in water for some reason and the water gets in the door pocket on the door on the driver's seat, the submersion detector arranged in the window operating unit on the driver's seat side detects the submersion, generates a submersion detection signal, and sends the signal to the drive control circuit. In response, the drive control circuit takes anti-flooding measures. Then, if the window open switch of the window operating unit on the driver's seat side is in the submerged state, the drive control circuit drives the motor to open the window of the driver's seat if the window open switch of the window operating unit on the driver's seat is manually operated within a certain period of time after the submersion took place, allowing the window on the driver's seat to open, and thus allow those trapped inside the submerged automobile to escape through this opened window.
The above-mentioned proposed power window apparatus allows the window on the driver's seat to open within a certain period of time by manually operating the window open switch of the window operating unit positioned near the driver's seat after the automobile has been submerged in water, even when water is getting in the door pocket of the door on the driver's seat.
If water gets inside the automobile, submerging the door pockets located near the driver's seat, the passenger seat, and the rear seats, the above-mentioned power window apparatus can take an anti-flooding measure only for the operating unit located near the driver's seat. Because the submersion detector and drive control circuit are connected only to the window operating unit located near the driver's seat, anti-flooding measures are not provided to the other window operating units. Therefore, if the water penetrates the window open switch of the window operating unit located near the passenger seat, and the rear seats, the manual operation of the window open switch on the side of these seats will not function, making it difficult for passengers to escape from the passenger and rear seats.